There is NO dark side of the moon! It all depends on your perspective... Half of the moon is virtually always in full sunlight - OBVIOUSLY!!! (The only exception, of course, being when there is a total eclipse of the moon. IE, when the moon is eclipsed by the earth...)
When there is what we call the "Dark Moon" - (the phase of the moon when it is between the "Old Moon" and the "New Moon") - the so-called dark side of the moon is actually in full daylight... As I said... It all depends on your perspective!!
The so-called "dark side of the moon" is simply the side of the moon that we never see, when viewed from Earth. One Luna "day" is equal to one Luna "year" - (the time it takes the moon to complete one full orbit of the Earth...) So we never get to see the so-called "dark side of the moon" unless we go up there in a space ship! Moral of the story? The Dark Side of the Moon is nothing more than the side of the moon that we never get to see - due to our narrow, restricted, earth-bound perspective...